1. Field of the Invention:
This invention relates generally to vehicle headlamp assemblies and more particularly, it relates to an improved snap-in headlamp adjustment assembly for positioning a vehicle headlamp which includes a snap-in adjuster nut secured to a vehicle frame so as to prevent both axial and rotational movement.
2. Description of the Prior Art:
As is well-known in the automotive industry, vehicle headlamp mounting and adjustment assemblies have been used for the past many years. Typically, the headlamp is mounted on a movable support housing and one or more threaded screw adjusters are used at different locations for moving the movable housing relative to a fixed vehicle frame a predetermined amount so as to position the headlamp as desired. In general, there would be at least two such threaded screw adjusters provided so as to position the headlamp in both the horizontal and vertical planes.
The prior art appears to be best exemplified in the following patents which were developed in a search directed to the subject matter of this application: U.S. Pat. Nos. 4,188,655; 4,599,681; and 5,063,481.
In U.S. Pat. No. 4,188,655 to Thomas G. Tallon et al. issued on Feb. 12, 1980, there is disclosed a vehicle headlamp and mounting assembly which includes a flanged fastening nut 46 (47) formed of a generally rectangular cross-section and a blunt tapered rearward portion by which it is inserted through an opening 61 and formed in a mounting panel 60. The fastening nut 46 has a pair of inwardly yieldable shoulders 48, 49 formed on its opposite sides and includes a pair of outwardly extending yieldable flanges or ears 51, 52 that bear against the front face of the mounting panel in which the nut is securely retained. The nut is molded of a plastic material and receives threadably therein an adjusting screw 42 (43).
In U.S. Pat. No. 4,599,681 to David R. McMahan et al. issued on Jul. 8, 1986, there is disclosed a vehicle headlamp assembly which includes a support housing 12, a headlamp support bracket 14 and a pair of rectangular vehicle headlamp units 16 and 18 mounted within the support bracket. The support housing 12 has a top wall 26 formed with a pair of upstanding ears 36 and 38. Each ear has a rectangular opening therein for rigidly retaining a snap-in type self-retaining plastic nut 40. The headlamp assembly includes three adjustment screws 20, 22 and 24 of which two are threadably received by the nuts 40 mounted in the ears 36, 38 which serve to adjustably position the support bracket and the headlamp units about a horizontal axis and a pair of inclined axes.
U.S. Pat. No. 5,063,481 to John P. Martin issued on Nov. 5, 1991, teaches a pivot assembly which is used to provide a pivot point for positioning a vehicular headlight mounted on a movable frame relative to a fixed frame. The pivot assembly includes a ball stud 50 that is secured to a selected one of the fixed and movable frames by a retainer clip 60. The clip is formed with an edge 28 which engages a transverse annular groove 10 in the ball stud so as to prevent axial movement and has at least one resilient arm 24 having a free-end 26 for engagement with one of a plurality of circumferentially spaced grooves 14. The plurality of grooves are in substantial transverse relationship to the annular groove 10 and cooperates with the free-end 26 of the arm 24 so as to prevent rotation of the ball stud 50 relative to an opening 41 formed in the fixed frame 36.
The present invention represents a significant improvement over the pivot assembly shown and described in the aforementioned '481 patent. In the assembly process of the pivot assembly of the '481 patent, the assembler is required to insert initially the elongated portion 8 of the ball stud 50 through the opening 41 in the fixed vehicle frame 36. Then, the assembler must reach behind the fixed frame 36 so as to install the metal retainer clip 60 into the annular groove 10 while holding constant pressure on the vehicle headlamp. As a result, there is encountered during manufacturing the disadvantage of increased assembly costs as well as component costs. Further, since the assembler has to get behind the vehicle frame in order to install the clip there must be provided a certain amount of clearance behind the vehicular frame which tends to restrict its design. Moreover, if the annular groove 10 on the ball stud is too large the clip will permit rattling of the ball stud or if the groove 10 is too small the clip will be difficult to install.
Accordingly, it would be desirable to provide a snap-in headlamp adjustment assembly for positioning a vehicle headlamp which can be quickly and easily installed by an ordinary user. It would also be expedient that the adjustment assembly prevent both axial and rotational movement relative to an opening formed in the fixed vehicle frame.